Mobile communication system, base station apparatus, mobile station apparatus and communication method

ABSTRACT

In a mobile communication system in which a plurality of component carriers are used, transmitting and receiving control information of HARQ effectively is realized. In a mobile communication system in which a base station apparatus ( 100 ) sets a plurality of downlink component carriers for a mobile station apparatus ( 200 ), the base station apparatus ( 100 ) transmits a downlink transport block to the mobile station apparatus ( 200 ) on one or a plurality of downlink component carriers among the plurality of downlink component carriers, and the mobile station apparatus transmits, to the base station apparatus ( 100 ), control information of HARQ for the downlink transport block on any one of physical uplink control channel resources corresponding to the one or plurality of downlink component carriers on which the downlink transport block has been transmitted.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of PCT International Application No.PCT/JP2010/071050 filed on Nov. 25, 2010, which claims the benefit toPatent Application No. 2009-269630 filed in Japan, on Nov. 27, 2009. Theentire contents of all of the above applications is hereby incorporatedby reference.

TECHNICAL FIELD

The present invention relates to a mobile communication system includinga base station apparatus and a mobile station apparatus and to acommunication method.

BACKGROUND ART

The 3GPP (3rd generation partnership project) is a project that examinesand prepares specifications of a mobile communication system based on anetwork in which W-CDMA (Wideband-code division multiple access) and GSM(Global system for mobile communications). In the 3GPP, W-CDMA system isstandardized as the third generation cellular mobile communicationsystem, and its services have been successively started. HSDPA(High-speed downlink packet access) in which a communication speed isfurther increased is also standardized, and its services are started. Inthe 3GPP, the evolution of the third generation radio access technology(hereinafter referred to as “LTE (long term evolution” or “EUTRA(evolved universal terrestrial radio access)”) and a broadband frequencyband are utilized, and thus a mobile communication system for realizingthe high speed transmission and reception of data (hereinafter referredto as an “LTE-A (long term evolution-advanced” or an “advanced-EUTRA”)is being examined.

As the communication system in the LTE, an OFDMA (orthogonal frequencydivision multiple access) system in which subcarriers orthogonal to eachother are used to perform user multiplexing and an SC-FDMA (singlecarrier-frequency division multiple access) system are being examined.Specifically, in a downlink, the OFDMA system which is a multi-carriercommunication system is proposed, and, in an uplink, the SC-FDMA systemwhich is a single-carrier communication system is proposed.

On the other hand, as the communication system in the LTE-A, in adownlink, the introduction of the OFDMA system is being examined, and,in an uplink, in addition to the SC-FDMA system, the introduction of theOFDMA system and a clustered-SC-FDMA (clustered-single carrier-frequencydivision multiple access, also referred to as DFTs-OFDM with spectrumdivision control) system is being examined. Here, in the LTE and theLTE-A, the SC-FDMA system proposed as an uplink communication system hasthe feature of being able to reduce a PAPR (peak to average power ratio:transmit power) when data is transmitted.

Whereas a frequency band used in a general mobile communication systemis contiguous, in the LTE-A, it is examined that a plurality ofcontiguous/discontiguous frequency bands (hereinafter referred to as a“carrier element, carrier component (CC)” or an “element carrier,component carrier (CC)”) are used in a composite manner and are managedas one broadband frequency band (frequency band aggregation: alsoreferred to as spectrum aggregation, carrier aggregation, frequencyaggregation or the like) (non-patent document 1). Furthermore, it isalso proposed that, in order for a base station apparatus and a mobilestation apparatus to more flexibly use a broadband frequency band toperform communications, a frequency band used in a downlinkcommunication and a frequency band used in an uplink communication aremade to have different frequency bandwidths (asymmetric frequency bandaggregation: asymmetric carrier aggregation) (non-patent document 2).

FIG. 7 is a diagram illustrating a mobile communication system on whichfrequency band aggregation has been performed in a conventionaltechnology. That, as shown in FIG. 7, a frequency band used in downlink(hereinafter also referred to as DL) communication and a frequency bandused in uplink (hereinafter also referred to as UL) communication aremade to have the same bandwidth is also referred to as symmetricfrequency band aggregation (symmetric carrier aggregation). As shown inFIG. 7, a base station apparatus and a mobile station apparatus use aplurality of carrier elements that are a contiguous and/or discontiguousfrequency band in a composite manner, and thereby can performcommunications in a broadband frequency band composed of a plurality ofcarrier elements. FIG. 7 shows, as an example, that a frequency band(hereinafter also referred to as a DL system band, a DL systembandwidth) used in downlink communication having a 100 MHz bandwidth iscomposed of five downlink carrier elements (DCC1: downlink componentcarrier 1, DCC2, DCC3, DCC4 and DCC 5) each having a 20 MHz bandwidth.FIG. 7 also shows, as an example, that a frequency band (hereinafteralso referred to as a UL system band, a UL system bandwidth) used inuplink communication having a 100 MHz bandwidth is composed of fiveuplink carrier elements (UCC1: uplink component carrier 1, UCC2, UCC3,UCC4 and UCC 5) each having a 20 MHz bandwidth.

In FIG. 7, in each of the downlink carrier elements, downlink channelssuch as a physical downlink control channel (hereinafter referred to asa PDCCH) and a physical downlink shared channel (hereinafter referred toas a PDSCH) are allocated. The base station apparatus can use the PDCCHto transmit, to the mobile station apparatus, control information(resource assignment information, MCS (modulation and coding scheme)information, HARQ (hybrid automatic repeat request) processinginformation and the like) for transmitting a downlink transport blocktransmitted using the PDSCH, and can use the PDSCH to transmit thedownlink transport block to the mobile station apparatus. In otherwords, in FIG. 7, the base station apparatus can transmit up to fivedownlink transport blocks at the maximum to the mobile station apparatusin the same subframe.

In each of the uplink carrier elements, uplink channels such as aphysical uplink control channel (hereinafter referred to as a PUCCH) anda physical uplink shared channel (hereinafter referred to as a PUSCH)are allocated. The mobile station apparatus can use the PUCCH and/or thePUSCH to transmit, to the base station apparatus, control information ofHARQ for the PDCCH and/or the downlink transport block (hereinafter alsoreferred to as control information of HARQ). Here, the controlinformation of HARQ refers to information (signal) indicating ACK/NACK(positive acknowledgment/negative acknowledgment) and/or information(signal) indicating DTX (discontiguous transmission). The informationindicating the DTX refers to information indicating that the mobilestation apparatus cannot detect the PDCCH transmitted from the basestation apparatus. Here, in FIG. 7, there may be a downlink/uplinkcarrier element where any of downlink/uplink channels such as the PDCCH,the PDSCH, the PUCCH and the PUSCH is not allocated.

Likewise, FIG. 8 is a diagram illustrating a mobile communication systemon which asymmetric frequency band aggregation (asymmetric carrieraggregation) has been performed in the conventional technology. As shownin FIG. 8, in the base station apparatus and the mobile stationapparatus, the frequency band used in the downlink communication and thefrequency band used in the uplink communication are made to havedifferent bandwidths, carrier elements which are a contiguous and/ordiscontiguous frequency band constituting these frequency bands are usedin a composite manner and thus communications can be performed in abroadband frequency band. FIG. 8 shows, as an example, that a frequencyband used in the downlink communication having a 100 MHz bandwidth iscomposed of five downlink carrier elements (DCC1, DCC2, DCC3, DCC4 andDCC 5) each having a 20 MHz bandwidth. FIG. 7 also shows that afrequency band used in the uplink communication having a 40 MHzbandwidth is composed of two uplink carrier elements (UCC1 and UCC 2)each having a 20 MHz bandwidth. In FIG. 8, in each of thedownlink/uplink carrier elements, downlink/uplink channels areallocated, and the base station apparatus can use a plurality of PDSCHsassigned by a plurality of PDCCHs, to transmit a plurality of downlinktransport blocks to the mobile station apparatus in the same subframe.The mobile station apparatus can use the PUCCH and/or the PUSCH totransmit control information of HARQ to the base station apparatus.

-   Non-patent document 1: “LTE-Advanced-LTE evolution towards    IMT-Advanced Technology components”, 3GPP TSG RAN IMT Advanced    Workshop, REV-080030, Apr. 7-8, 2008.-   Non-patent document 2: “Initial Access Procedure for Asymmetric    Wider Bandwidth in LTE-Advanced”, 3GPP TSG RAN WG1 Meeting #55,    R1-084249, Nov. 10-14, 2008.

DISCLOSURE OF THE INVENTION

However, in the conventional technology, it is not specifically clearhow the base station apparatus and the mobile station apparatus transmitand receive control information of HARQ when communication is performedusing a broadband frequency band composed of a plurality of carrierelements.

When the mobile station apparatus transmits the control information ofHARQ to the base station apparatus, consideration needs to be given totransmit power of the mobile station apparatus. For example, in orderfor the mobile station apparatus to use a large number of uplink carrierelements (using a large number of channels) in the same subframe totransmit a plurality of pieces of control information of HARQ, it isnecessary to transmit the control information of HARQ with an extremelyhigh power. For example, if the mobile station apparatus uses all fivePUCCHs allocated in each of the five uplink carrier elements in the samesubframe, to transmit the control information of HARQ to the basestation apparatus, the mobile station apparatus needs to have an abilityto transmit the control information of HARQ with an extremely highpower. Increasing the ability of transmit power in the mobile stationapparatus leads to increasing the ability of power amplifier (PA) or thelike incorporated in the mobile station apparatus, which increases thecost of mobile station apparatus.

As described above, in the conventional technology, since it is notspecifically clear how the base station apparatus and the mobile stationapparatus transmit and receive the control information of HARQ whencommunication is performed using a broadband frequency band composed ofa plurality of carrier elements, the transmit power of the mobilestation apparatus is disadvantageously increased.

The present invention is made in view of the foregoing situation; anobject of the present invention is to provide a mobile communicationsystem, a base station apparatus, a mobile station apparatus and acommunication method in which the base station apparatus and the mobilestation apparatus can effectively transmit and receive the controlinformation of HARQ in consideration of the transmit power of the mobilestation apparatus when communication is performed using a broadbandfrequency band composed of a plurality of carrier elements.

(1) To achieve the above object, the present invention takes thefollowing measures. Specifically, the mobile communication system of thepresent invention is a mobile communication system in which a basestation apparatus sets a plurality of downlink component carriers for amobile station apparatus, wherein the base station apparatus transmits adownlink transport block to the mobile station apparatus on one or aplurality of downlink component carriers among the plurality of downlinkcomponent carriers, and the mobile station apparatus transmits, to thebase station apparatus, control information of HARQ for the downlinktransport block in any one of physical uplink control channel resourcescorresponding to the one or plurality of downlink component carriers onwhich the downlink transport block has been transmitted.

(2) Further, the mobile communication system of the present invention isa mobile communication system in which a base station apparatus sets aplurality of downlink component carriers for a mobile station apparatus,wherein the base station apparatus transmits, in a physical downlinkshared channel, a downlink transport block to the mobile stationapparatus on one or a plurality of downlink component carriers among theplurality of downlink component carriers, and the mobile stationapparatus transmits, to the base station apparatus, control informationof HARQ for the downlink transport block in any one of physical uplinkcontrol channel resources corresponding to the physical downlink sharedchannel.

(3) Further, in the mobile communication system of the presentinvention, the control information of HARQ is information indicatingACK/NACK.

(4) Further, in the mobile communication system of the presentinvention, the control information of HARQ is information indicating DTX(discontiguous transmission).

(5) Further, the base station apparatus of the present invention is abase station apparatus that sets a plurality of downlink componentcarriers for a mobile station apparatus, the base station apparatuscomprising: a unit that transmits a downlink transport block to themobile station apparatus on one or a plurality of downlink componentcarriers among the plurality of downlink component carriers; and a unitthat receives, from the base station apparatus, control information ofHARQ for the downlink transport block in any one of physical uplinkcontrol channel resources corresponding to the one or plurality ofdownlink component carriers on which the downlink transport block hasbeen transmitted.

(6) Further, the base station apparatus of the present invention is abase station apparatus that sets a plurality of downlink componentcarriers for a mobile station apparatus, the base station apparatuscomprising: a unit that transmits, in a physical downlink sharedchannel, a downlink transport block to the mobile station apparatus onone or a plurality of downlink component carriers among the plurality ofdownlink component carriers; and a unit that receives, from the mobilestation apparatus, control information of HARQ for the downlinktransport block in any one of physical uplink control channel resourcescorresponding to the physical downlink shared channel.

(7) Further, in the base station apparatus of the present invention, thecontrol information of HARQ is information indicating ACK/NACK.

(8) Further, in the base station apparatus of the present invention, thecontrol information of HARQ is information indicating DTX (discontiguoustransmission).

(9) Further, the mobile station apparatus of the present invention is amobile station apparatus for which a plurality of downlink componentcarriers is set by a base station apparatus, the mobile stationapparatus comprising: a unit that receives a downlink transport blockfrom the base station apparatus on one or a plurality of downlinkcomponent carriers among the plurality of downlink component carriers;and a unit that transmits, to the base station apparatus, controlinformation of HARQ for the downlink transport block in any one ofphysical uplink control channel resources corresponding to the one orplurality of downlink component carriers on which the downlink transportblock has been transmitted.

(10) Further, the mobile station apparatus of the present invention is amobile station apparatus for which a plurality of downlink componentcarriers is set by a base station apparatus, the mobile stationapparatus comprising: a unit that receives, in a physical downlinkshared channel, a downlink transport block from the base stationapparatus on one or a plurality of downlink component carriers among theplurality of downlink component carriers; and a unit that transmits, tothe base station apparatus, control information of HARQ for the downlinktransport block in any one of physical uplink control channel resourcescorresponding to the physical downlink shared channel.

(11) Further, in the mobile station apparatus of the present invention,the control information of HARQ is information indicating ACK/NACK.

(12) Further, in the mobile station apparatus of the present invention,the control information of HARQ is information indicating DTX(discontiguous transmission).

(13) Further, the communication method of the present invention is acommunication method of a base station apparatus for setting a pluralityof downlink component carriers for a mobile station apparatus,comprising the steps of: transmitting a downlink transport block to themobile station apparatus on one or a plurality of downlink componentcarriers among the plurality of downlink component carriers; andreceiving, from the mobile station apparatus, control information ofHARQ for the downlink transport block in any one of physical uplinkcontrol channel resources corresponding to the one or plurality ofdownlink component carriers on which the downlink transport block hasbeen transmitted.

(14) Further, the communication method of the present invention is acommunication method of a base station apparatus for setting a pluralityof downlink component carriers for a mobile station apparatus,comprising the steps of: transmitting, in a physical downlink sharedchannel, a downlink transport block to said mobile station apparatus onone or a plurality of downlink component carriers among said pluralityof downlink component carriers; and receiving, from said mobile stationapparatus, control information of HARQ for said downlink transport blockin any one of physical uplink control channel resources corresponding tosaid physical downlink shared channel.

(15) Further, in the communication method of the present invention, thecontrol information of HARQ is information indicating ACK/NACK.

(16) Further, in the communication method of the present invention, thecontrol information of HARQ is information indicating DTX (discontiguoustransmission).

(17) Further, the communication method of the present invention is acommunication method of a mobile station apparatus in which a pluralityof downlink component carriers is set by a base station apparatus,comprising the steps of: receiving a downlink transport block from thebase station apparatus on one or a plurality of downlink componentcarriers among the plurality of downlink component carriers; andtransmitting, to the base station apparatus, control information of HARQfor the downlink transport block in any one of physical uplink controlchannel resources corresponding to the one or plurality of downlinkcomponent carriers on which the downlink transport block has beentransmitted.

(18) Further, the communication method of the present invention is acommunication method of a mobile station apparatus in which a pluralityof downlink component carriers is set by a base station apparatus,comprising the steps of: receiving, in a physical downlink sharedchannel, a downlink transport block from the base station apparatus onone or a plurality of downlink component carriers among the plurality ofdownlink component carriers; and transmitting, to the base stationapparatus, control information of HARQ for the downlink transport blockin any one of physical uplink control channel resources corresponding tothe physical downlink shared channel.

(19) Further, in the communication method of the present invention, thecontrol information of HARQ is information indicating ACK/NACK.

(20) Further, in the communication method of the present invention, thecontrol information of HARQ is information indicating DTX (discontiguoustransmission).

According to the present invention, the base station apparatus and themobile station apparatus that perform communications using a broadbandfrequency band composed of a plurality of carrier elements caneffectively transmit and receive control information of HARQ.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram conceptually showing the configuration of a physicalchannel:

FIG. 2 is a block diagram showing a schematic configuration of a basestation apparatus according to an embodiment of the present invention;

FIG. 3 is a block diagram showing a schematic configuration of a mobilestation apparatus according to the embodiment of the present invention;

FIG. 4 is a diagram showing an example of a mobile communication systemapplicable to a first embodiment;

FIG. 5 is a diagram showing another example of the mobile communicationsystem applicable to the first embodiment;

FIG. 6 is a diagram showing an example of a mobile communication systemapplicable to a second embodiment;

FIG. 7 is a diagram illustrating an example of a mobile communicationsystem on which frequency band aggregation has been performed in aconventional technology;

FIG. 8 is a diagram illustrating an example of a mobile communicationsystem on which asymmetric frequency band aggregation has been performedin the conventional technology.

BEST MODES FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will now be described withreference to accompanying drawings. FIG. 1 is a diagram showing anexample of the configuration of a channel in the embodiment of thepresent invention. A downlink physical channel is configured with aphysical broadcast channel (PBCH), a physical downlink control channel(PDCCH), a physical downlink shared channel (PDSCH), a physicalmulticast channel (PMCH), a physical control format indicator channel(PCFICH) and a physical hybrid ARQ indicator channel (PHICH). An uplinkphysical channel is configured with a physical uplink shared channel(PUSCH), a physical uplink control channel (PUCCH) and a physical randomaccess channel (PRACH).

The physical broadcast channel (PBCH) maps a broadcast channel (BCH) atintervals of 40 milliseconds. Blind detection is performed on the timingof 40 milliseconds. In other words, explicit signaling is not performedfor provision of timing. A subframe including the physical broadcastchannel (PBCH) is decodable by itself (self-decodable).

The physical downlink control channel (PDCCH) is a channel used fornotification (transmission) of the resource assignment of the physicaldownlink shared channel (PDSCH), hybrid automatic repeat request (HARQ)information for downlink data and an uplink transmission permission thatis the resource assignment of the physical uplink shared channel (PUSCH)to a mobile station apparatus. The PDCCH is composed of a plurality ofcontrol channel elements (CCE); the mobile station apparatus detects thePDCCH composed of the CCEs to thereby receive the PDCCH from the basestation apparatus. The CCE is composed of a plurality of resourceelement groups (REG, also referred to as a mini-CCE) that is spread infrequency and time domains. Here, the resource element refers to a unitresource that is composed of one OFDM symbols (time component) and onesubcarrier (frequency component); for example, in a frequency domainwithin the same OFDM symbol, the REG is composed of four downlinkresource elements contiguous in the frequency domain, other than adownlink pilot channel. For example, one PDCCH is composed of 1, 2, 4 or8 CCEs in which numbers (CCE indices) for identification of CCEs arecontiguous.

For each of the mobile station apparatuses and each of types, the PDCCHis individually subjected to coding (separate coding). In other words,the mobile station apparatus detects a plurality of PDCCHs, and acquiresinformation indicating the downlink or uplink resource assignment andother control signals. The value of a CRC (cyclical redundancy check)that can identify a format is provided to each PDCCH; the mobile stationapparatus performs the CRC on each of a set of CCEs that can constitutethe PDCCH, and acquires the PDCCH in which the CRC has been successful.This is also referred to as blind decoding; the range of a set of CCEson which the mobile station apparatus performs the blind decoding andwhich can constitute the PDCCH is also referred to as a search space. Inother words, the mobile station apparatus performs the blind decoding onCCEs in the search space to detect the PDCCH.

When the PDCCH is used for indicating the resource assignment of thephysical downlink shared channel (PDSCH), the mobile station apparatusreceives, according to the resource assignment indicated by the PDCCHfrom the base station apparatus, using the physical downlink sharedchannel (PDSCH), data (downlink data (downlink shared channel (DL-SCH))and/or downlink control data (downlink control information). In otherwords, this PDCCH is used for transmitting a signal (hereinafterreferred to as a “downlink transmission permission signal” or a“downlink grant”) for performing resource assignment on the downlink.When the PDCCH is used for indicating the resource assignment of thephysical uplink shared channel (PUSCH), the mobile station apparatustransmits, according to the resource assignment indicated by the PDCCHfrom the base station apparatus, using the physical uplink sharedchannel (PUSCH), data (uplink data (uplink shared channel (UL-SCH))and/or uplink control data (uplink control information). In other words,this PDCCH is used for transmitting a signal (hereinafter referred to asan “uplink transmission permission signal” or an “uplink grant”) forpermitting data transmission for the uplink.

The physical downlink shared channel (PDSCH) is a channel used fortransmitting the downlink data (down link shared channel: DL-SCH) orpaging information (paging channel: PCH). The physical multicast channel(PMCH) is a channel utilized for transmitting a multicast channel (MCH);a downlink reference signal, an uplink reference signal and a physicaldownlink synchronization signal are allocated separately.

Here, the downlink data (DL-SCH) refers to, for example, thetransmission of user data; the DL-SCH is a transport channel. In theDL-SCH, the HARQ and dynamic adaptation radio link control aresupported, and beam forming can be utilized. In the DL-SCH, dynamicresource assignment and semi-static resource assignment are supported.

The physical uplink shared channel (PUSCH) is a channel used for mainlytransmitting uplink data (uplink shared channel: UL-SCH). When the basestation apparatus performs scheduling on the mobile station apparatus,the uplink control information (uplink control signal) is alsotransmitted using the PUSCH. This uplink control information includes:channel state information CSI (or channel statistical information) thatindicates the channel state of the downlink; a downlink channel qualityindicator CQI; a precoding matrix indicator PMI; a rank indicator RI;and control information of HARQ for the PDCCH and/or downlink transportblock (information indicating ACK/NACK and/or information indicatingDTX).

Here, the uplink data (UL-SCH) refers to, for example, the transmissionof user data; the UL-SCH is a transport channel. In the UL-SCH, the HARQand dynamic adaptation radio link control are supported, and beamforming can be utilized. In the UL-SCH, dynamic resource assignment andstatic resource assignment are supported.

In the uplink data (UL-SCH) and the downlink data (DL-SCH), a radioresource control signaling (hereinafter referred to as “RRC signaling”)exchanged between the base station apparatus and the mobile stationapparatus, a MAC (medium access control) control element and the likemay be included.

The physical uplink control channel (PUCCH) is a channel used fortransmitting uplink control information (uplink control signal). Here,for example, the uplink control information includes: the channel stateinformation CSI that indicates the channel state of the downlink; thedownlink channel quality indicator CQI; the precoding matrix indicatorPMI; the rank indicator RI; a scheduling request (SR) for the mobilestation apparatus to request resource assignment for transmitting theuplink data (requesting the transmission in the UL-SCH); and the controlinformation of HARQ for the PDCCH and/or downlink transport block(information indicating ACK/NACK and/or information indicating DTX).

The physical control format indicator channel (PCFICH) is a channelutilized for the notification of the number of OFDM symbols used for thePDCCH to the mobile station apparatus; it is transmitted in eachsubframe. The physical hybrid ARQ indicator channel (PHICH) is a channelutilized for the transmission of ACK/NACK used on HARQ of the uplinkdata. The physical random access channel (PRACH) is a channel used forthe transmission of a random access preamble, and has a guard time. Asshown in FIG. 1, the mobile communication system of the presentembodiment includes the base station apparatus 100 and the mobilestation apparatuses 200 (200-1 to 200-3).

[Configuration of the Base Station Apparatus]

FIG. 2 is a block diagram showing a schematic configuration of the basestation apparatus 100 according to the embodiment of the presentinvention. The base station apparatus 100 includes a data controlportion 101, a transmission data modulation portion 102, a radio portion103, a scheduling portion 104, a channel estimation portion 105, areception data demodulation portion 106, a data extraction portion 107,an higher layer 108 and an antenna 109. The radio portion 103, thescheduling portion 104, the channel estimation portion 105, thereception data demodulation portion 106, the data extraction portion107, the higher layer 108 and the antenna 109 constitute a receptionportion; the data control portion 101, the transmission data modulationportion 102, the radio portion 103, the scheduling portion 104, thehigher layer 108 and the antenna 109 constitute a transmission portion.

The antenna 109, the radio portion 103, the channel estimation portion105, the reception data demodulation portion 106 and the data extractionportion 107 perform processing on an uplink physical layer. The antenna109, the radio portion 103, the transmission data modulation portion 102and the data control portion 101 perform processing on a downlinkphysical layer.

The data control portion 101 receives a transport channel from thescheduling portion 104. The data control portion 101 maps the transportchannel and a signal and a channel generated in the physical layer onthe physical channel based on scheduling information input from thescheduling portion 104. Each piece of data mapped as described above isoutput to the transmission data modulation portion 102.

The transmission data modulation portion 102 modulates the transmissiondata into an OFDM system. The transmission data modulation portion 102performs, on the data input from the data control portion 101, based onthe scheduling information from the scheduling portion 104 and amodulation scheme and a coding scheme corresponding to each PRB, signalprocessing such as data modulation, coding, serial/parallel conversionof the input signal, IFFT (inverse fast Fourier transform) processing,CP (cyclic prefix) insertion and filtering, generates the transmissiondata and outputs it to the radio portion 103. Here, the schedulinginformation includes downlink physical resource block PRB assignmentinformation such as physical resource block position informationcomposed of frequency and time; the modulation scheme and the codingscheme corresponding to each PRB include information such as themodulation scheme: 16 QAM and the coding rate: a ⅔ coding rate.

The radio portion 103 upconverts the modulation data input from thetransmission data modulation portion 102 into radio frequency togenerate a radio signal, and transmits it to the mobile stationapparatus 200 through the antenna 109. The radio portion 103 alsoreceives the uplink radio signal from the mobile station apparatus 200through the antenna 109, and downconverts it into a base band signal andoutputs the reception data to the channel estimation portion 105 and thereception data demodulation portion 106.

The scheduling portion 104 performs processing on a medium accesscontrol (MAC) layer. The scheduling portion 104 performs mapping on alogical channel and a transport channel, scheduling on the downlink andthe uplink (such as the HARQ processing and the selection of a transportformat) and the like. In order for the processing portions of theindividual physical layers to be integrally controlled, in thescheduling portion 104, interfaces (not shown) are present between thescheduling portion 104 and the antenna 109, the radio portion 103, thechannel estimation portion 105, the reception data demodulation portion106, the data control portion 101, the transmission data modulationportion 102 and the data extraction portion 107.

In the downlink scheduling, based on feedback information (such asuplink channel state information (CSI, CQI, PMI, RI) and ACK/NACKinformation for the downlink data) received from the mobile stationapparatus 200, available information on the PRB of each mobile stationapparatus 200, buffer conditions, scheduling information input from thehigher layer 108 and the like, the scheduling portion 104 performsselection processing on a downlink transport format for modulating eachpiece of data (such as a transmission form, that is, the assignment of aphysical resource block and the modulation scheme, the coding scheme andthe like), retransmitting control on HARQ and the generation of thescheduling information used in the downlink. The scheduling informationused in the scheduling of the downlink is output to the data controlportion 101.

In the uplink scheduling, based on the result of the estimation of thechannel state (a radio channel state) of the uplink output by thechannel estimation portion 105, the request of the resource assignmentfrom the mobile station apparatus 200, available information on the PRBof each mobile station apparatus 200, the scheduling information inputfrom the higher layer 108 and the like, the scheduling portion 104performs selection processing on an uplink transport format formodulating each piece of data (such as a transmission form, that is, theassignment of a physical resource block and the modulation scheme, thecoding scheme and the like) and the generation of the schedulinginformation used in the uplink scheduling. The scheduling informationused in the uplink scheduling is output to the data control portion 101.

Moreover, the scheduling portion 104 maps the downlink logical channelinput from the higher layer 108 on the transport channel, and outputs itto the data control portion 101. Furthermore, the scheduling portion 104processes, as necessary, control data input from the data extractionportion 107 and acquired in the uplink and the transport channel, andthen maps them on the uplink logical channel and outputs them to thehigher layer 108.

In order to demodulate the uplink data, the channel estimation portion105 estimates the channel state of the uplink from uplink demodulationreference signal (DRS), and outputs the result of the estimation to thereception data demodulation portion 106. Furthermore, in order toperform the uplink scheduling, the channel estimation portion 105estimates the channel state of the uplink from uplink measurementreference signal (SRS: sounding reference signal), and outputs theresult of the estimation to the scheduling portion 104.

The reception data demodulation portion 106 also serves as an OFDMdemodulation portion and/or a DFT-Spread-OFDM (DFT-S-OFDM) demodulationportion that demodulates the reception data modulated into an OFDMsystem and/or a SC-FDMA system. Based on the result of the estimation ofthe channel state of the uplink input from the channel estimationportion 105, the reception data demodulation portion 106 performs, onthe modulation data input from the radio portion 103, signal processingsuch as DFT conversion, subcarrier mapping, IFFT conversion andfiltering, performs demodulation processing on it and outputs it to thedata extraction portion 107.

The data extraction portion 107 checks whether the data input from thereception data demodulation portion 106 is correct or wrong, and outputsthe result of the checking (positive signal ACK/negative signal NACK) tothe scheduling portion 104. The data extraction portion 107 alsoseparates the data input from the reception data demodulation portion106 into the transport channel and control data on the physical layer,and outputs them to the scheduling portion 104. The separated controldata includes: the channel state information CSI notified from themobile station apparatus 200; the downlink channel quality indicatorCQI; the precoding matrix indicator PMI; the rank indicator RI; thecontrol information of HARQ and the scheduling request.

The higher layer 108 performs processing on a packet data convergenceprotocol (PDCP) layer, a radio link control (RLC) layer and a radioresource control (RRC) layer. In order for the processing portions ofthe lower layers to be integrally controlled, in the higher layer 108,interfaces (not shown) are present between the higher layer 108 and thescheduling portion 104, the antenna 109, the radio portion 103, thechannel estimation portion 105, the reception data demodulation portion106, the data control portion 101, the transmission data modulationportion 102 and the data extraction portion 107.

The higher layer 108 includes a radio resource control portion 110 (alsoreferred to as a control portion). The radio resource control portion110 performs management on various types of setting information,management on system information, paging control, management on thestate of communication of each mobile station apparatus 200, movementmanagement such as handover, management on the buffer conditions of eachmobile station apparatus 200, management on the connection setting ofunicast and multicast bearers, management on mobile station identifiers(UEID) and the like. The higher layer 108 exchanges information foranother base station apparatus and information for an upper node.

[Configuration of the Mobile Station Apparatus 200]

FIG. 3 is a block diagram showing a schematic configuration of themobile station apparatus 200 according to the embodiment of the presentinvention. The mobile station apparatus 200 includes a data controlportion 201, a transmission data modulation portion 202, a radio portion203, a scheduling portion 204, a channel estimation portion 205, areception data demodulation portion 206, a data extraction portion 207,an higher layer 208 and an antenna 209. The data control portion 201,the transmission data modulation portion 202, the radio portion 203, thescheduling portion 204, the higher layer 208 and the antenna 209constitute a transmission portion; the radio portion 203, the schedulingportion 204, the channel estimation portion 205, the reception datademodulation portion 206, the data extraction portion 207, the higherlayer 208 and the antenna 209 constitute a reception portion.

The data control portion 201, the transmission data modulation portion202 and the radio portion 203 perform processing on an uplink physicallayer. The radio portion 203, the channel estimation portion 205, thereception data demodulation portion 206 and the data extraction portion207 perform processing on a downlink physical layer.

The data control portion 201 receives a transport channel from thescheduling portion 204. The data control portion 201 maps the transportchannel and a signal and a channel generated in the physical layer onthe physical channel based on scheduling information input from thescheduling portion 204. Each piece of data mapped as above is output tothe transmission data modulation portion 202.

The transmission data modulation portion 202 modulates the transmissiondata into the OFDM system and/or the SC-FDMA system. The transmissiondata modulation portion 202 performs, on the data input from the datacontrol portion 201, signal processing such as data modulation, DFT(discrete Fourier transform) processing, subcarrier mapping, IFFT(inverse fast Fourier transform) processing, CP insertion and filtering,generates the transmission data and outputs it to the radio portion 203.

The radio portion 203 upconverts the modulation data input from thetransmission data modulation portion 202 into radio frequency togenerate a radio signal, and transmits it to the base station apparatus100 through the antenna 209. The radio portion 203 also receives,through the antenna 209, the radio signal modulated by the downlink datafrom the base station apparatus 100, and downconverts it into a baseband signal and outputs the reception data to the channel estimationportion 205 and the reception data demodulation portion 206.

The scheduling portion 204 performs processing on a medium accesscontrol (MAC) layer. The scheduling portion 204 performs mapping betweena logical channel and a transport channel, scheduling on the downlinkand the uplink (such as the HARQ processing and the selection of atransport format) and the like. In order for the processing portions ofthe individual physical layers to be integrally controlled, in thescheduling portion 204, interfaces (not shown) are present between thescheduling portion 204 and the antenna 209, the data control portion201, the transmission data modulation portion 202, the channelestimation portion 205, the reception data demodulation portion 206, thedata extraction portion 207 and the radio portion 203.

In the downlink scheduling, based on the scheduling information (thetransport format and the HARQ retransmission information) from the basestation apparatus 100 and the higher layer 208 and the like, thescheduling portion 204 performs reception control on the transportchannel and the physical signal and the physical channel and thegeneration of the scheduling information used on HARQ retransmissioncontrol and the downlink scheduling. The scheduling information used inthe downlink scheduling is output to the data control portion 201.

In the uplink scheduling, based on the buffer conditions of the uplinkinput from the higher layer 208, the uplink scheduling information (thetransport format, the HARQ retransmission information and the like) fromthe base station apparatus 100 input from the data extraction portion207, the scheduling information input from the higher layer 208 and thelike, the scheduling portion 204 performs scheduling processing formapping the uplink logical channel input from the higher layer 208 onthe transport channel and the generation of the scheduling informationused in the uplink scheduling. With respect to the uplink transportformat, information notified from the base station apparatus 100 isutilized. The scheduling information described above is output to thedata control portion 201.

Moreover, the scheduling portion 204 maps the uplink logical channelinput from the higher layer 208 on the transport channel, and outputs itto the data control portion 201. The scheduling portion 204 alsooutputs, to the data control portion 201, the downlink channel stateinformation CSI input from the channel estimation portion 205, thedownlink channel quality indicator CQI, the precoding matrix indicatorPMI, the rank indicator RI and the result of the CRC check input fromthe data extraction portion 207. Furthermore, the scheduling portion 204processes, as necessary, control data input from the data extractionportion 207 and acquired in the downlink and the transport channel, andthen maps them on the downlink logical channel and outputs them to thehigher layer 208.

In order to demodulate the downlink data, the channel estimation portion205 estimates the channel state of the downlink from the downlinkreference signal (RS), and outputs the result of the estimation to thereception data demodulation portion 206. In order to notify the basestation apparatus 100 of the result of the estimation of the channelstate (radio channel state) of the downlink, the channel estimationportion 205 estimates the channel state of the downlink from thedownlink reference signal (RS), and outputs the result of the estimationto the scheduling portion 204 as the downlink channel state informationCSI, the downlink channel quality indicator CQI, the precoding matrixindicator PMI and the rank indicator RI.

The reception data demodulation portion 206 demodulates the receptiondata modulated into the OFDM system. The reception data demodulationportion 206 performs, based on the result of the estimation of thechannel state of the downlink input from the channel estimation portion205, the demodulation processing on the modulation data input from theradio portion 203, and outputs it to the data extraction portion 207.

The data extraction portion 207 performs CRC check on the data inputfrom the reception data demodulation portion 206, checks whether or notit is correct and outputs the result of the checking (positiveacknowledgment ACK/negative acknowledgment NACK) to the schedulingportion 204. The data extraction portion 207 also separates the datainput from the reception data demodulation portion 206 into thetransport channel and control data on the physical layer, and outputsthem to the scheduling portion 204. The separated control data includesthe scheduling information such as the resource assignment of thedownlink or the uplink and the HARQ control information on the uplink.

The higher layer 208 performs processing on a packet data convergenceprotocol (PDCP) layer, a radio link control (RLC) layer and a radioresource control (RRC) layer. In order for the processing portions ofthe lower layers to be integrally controlled, in the higher layer 208,interfaces (not shown) are present between the higher layer 208 and thescheduling portion 204, the antenna 209, the data control portion 201,the transmission data modulation portion 202, the channel estimationportion 205, the reception data demodulation portion 206, the dataextraction portion 207 and the radio portion 203.

The higher layer 208 includes a radio resource control portion 210 (alsoreferred to as a control portion). The radio resource control portion210 performs management on various types of setting information,management on system information, paging control, management on thestate of communication of the its station, movement management such ashandover, management on the buffer conditions, management on theconnection setting of unicast and multicast bearers and management onmobile station apparatus identifiers (UEID).

First Embodiment

A first embodiment of the mobile communication system using the basestation apparatus 100 and the mobile station apparatuses 200 will now bedescribed. In the first embodiment, the base station apparatus 100semi-statically sets the first PUCCH to the mobile station apparatus200, and dynamically sets the second PUCCH to the mobile stationapparatus 200 in the same subframe as the subframe in which the firstPUCCH is set; the mobile station apparatus 200 uses the first PUCCH andthe second PUCCH, and thereby can transmit the control information ofHARQ to the base station apparatus 100. The base station apparatus 100semi-statically sets the first PUCCH to the mobile station apparatus200, and dynamically sets the second PUCCH to the mobile stationapparatus 200 in the same subframe as the subframe in which the firstPUCCH is set; the mobile station apparatus 200 uses the first PUCCH orthe second PUCCH, and thereby can transmit the control information ofHARQ to the base station apparatus 100. Here, the mobile stationapparatus 200 bundles (bunches or clumps) the control information ofHARQ, and thereby can transmit it to the base station apparatus 100. Themobile station apparatus 200 also multiples (using a plurality of bits)the control information of HARQ, and thereby can transmit it to the basestation apparatus 100. Here, the control information of HARQ (controlsignal of HARQ) transmitted by the mobile station apparatus 200 to thebase station apparatus 100 refers to information (signal) indicatingACK/NACK for the PDCCH and/or the downlink transport block transmittedfrom the base station apparatus 100 and/or information (signal)indicating the DTX. The DTX refers to information (signal) indicatingthat the mobile station apparatus 200 cannot detect the PDCCH from thebase station apparatus 100.

Although, in the following description of the first embodiment, afrequency band is defined as a bandwidth (Hz), it may be defined as thenumber of resource blocks (RB) composed of frequencies and times. In thepresent embodiment, a carrier element (hereinafter also referred to as a“carrier component,” an “element carrier” or a “component carrier”)refers to a (narrowband) frequency band aggregated when the base stationapparatus 100 and the mobile station apparatus 200 performscommunication using a broadband frequency band (it may be a systemband). The base station apparatus 100 and the mobile station apparatus200 aggregates a plurality of carrier elements to form a broadbandfrequency band, and use the carrier elements in a composite manner andthereby can realize high-speed data communication (the transmission andreception of information) (frequency band aggregation). For example, thebase station apparatus 100 and the mobile station apparatus 200aggregate five carrier elements each having a frequency width of 20 MHzto form a frequency band having a broadband frequency width of 100 MHz,and use the five carrier elements in a composite manner and thereby canperform communication.

The carrier element refers to each of (narrowband) frequency bands (forexample, frequency bands each having a bandwidth of 20 MHz) constitutingthis broadband frequency band (for example, a frequency band having abandwidth of 100 MHz). The carrier element also refers to each of(central) carrier frequencies of the (narrowband) frequency bandsconstituting this broadband frequency band. In other words, the downlinkcarrier element has a partial band (width) of the frequency bandavailable when the base station apparatus 100 and the mobile stationapparatus 200 transmit and receive the downlink information; the uplinkcarrier element has a partial band (width) of the frequency bandavailable when the base station apparatus 100 and the mobile stationapparatus 200 transmit and receive the uplink information. The carrierelement may also be defined as a unit for constituting a specificphysical channel (for example, the PDCCH, the PDSCH, the PUCCH or thePUSCH).

Here, the carrier element may be allocated in a contiguous frequencyband or in a discontiguous frequency band; a plurality of carrierelements that are a contiguous and/or a discontiguous frequency band areaggregated, and thus it is possible to form a broadband frequency band.It is not necessary that a frequency band (which may be the DL systemband or the DL system bandwidth) which is composed of the downlinkcarrier elements and which is used in the downlink communication beequal in the bandwidth to a frequency band (which may be the UL systemband or the UL system bandwidth) which is composed of the uplink carrierelements and which is used in the uplink communication. Even if thefrequency band used in the downlink communication is different in thebandwidth from the frequency band used in the uplink communication, thebase station apparatus 100 and the mobile station apparatus 200 use thecarrier elements in a composite manner and thereby can performcommunication (asymmetric frequency band aggregation).

FIG. 4 is a diagram showing an example of the mobile communicationsystem to which the first embodiment is applicable. FIG. 4 shows that,as an example illustrating the first embodiment, a frequency band havinga bandwidth of 100 MHz and used in the downlink communication iscomposed of five downlink carrier elements (DCC1, DCC2, DCC3, DCC4 andDCC5), each having a bandwidth of 20 MHz. FIG. 4 also shows that afrequency band having a bandwidth of 100 MHz and used in the uplinkcommunication is composed of five uplink carrier elements (UCC1, UCC2,UCC3, UCC4 and UCC5), each having a bandwidth of 20 MHz. In FIG. 4, oneach of the downlink/uplink carrier elements, a downlink/uplink channelis mapped. Here, in FIG. 4, a downlink/uplink carrier element may bepresent on which any of downlink/uplink channels such as the PDCCH, thePDSCH, the PUCCH and the PUSCH is not mapped.

In FIG. 4, the base station apparatus 100 uses a plurality of PDCCHs oneach of the downlink carrier elements, and thereby can set (allocate) aplurality of PDSCHs in the same subframe. For example, the base stationapparatus 100 uses, on each of DCC1, DCC2, DCC3, DCC4 and DCC5, fivePDCCHs (four PDCCHs indicated by black areas and one PDCCH indicated byoblique lines), and thereby can set the PDSCH on each of the DCC1, theDCC2, the DCC3, the DCC4 and the DCC5. Here, the base station apparatus100 sets a plurality of PDCCHs on one carrier element in the downlink(using a plurality of PDCCHs, each PDCCH is coded separately), andthereby can also set a plurality of PDSCHs. For example, the basestation apparatus 100 uses three PDCCHs set on the DCC3, and thereby canset three PDSCHs (for example, can set PDSCHs on the DCC1, the DCC2 andDCCC4) in the same subframe.

Here, in order to use a plurality of PDCCHs set on one carrier elementin the downlink and thereby set a plurality of PDSCHs, the base stationapparatus 100 transmits component carrier identifier information(hereinafter also referred to “CII: carrier indicator information” or“CIF: carrier indicator field”) on the PDCCHs. In other words, the basestation apparatus 100 transmits the component carrier identifierinformation indicating which carrier element is used for transmission ofthe PDSCH on each of the PDCCH. For example, the base station apparatus100 transmits, on each of three PDCCHs in the DCC3, component carrieridentifier information indicating the setting of the PDSCH on the DCC1,component carrier identifier information indicating the setting of thePDSCH on the DCC2 and component carrier identifier informationindicating the setting of the PDSCH on the DCC4.

Furthermore, the base station apparatus 100 uses a plurality of PDSCHson each carrier element in the downlink, and thereby can transmit, inthe same subframe, a plurality of downlink transport blocks to themobile station apparatus 200. For example, the base station apparatus100 uses five PDSCHs on the DCC1, the DCC2, the DCC3, the DCC4 and theDCC5, and thereby can transmit, in the same subframe, downlink transportblocks (up to five at the maximum) to the mobile station apparatus 200.

In FIG. 4, the mobile station apparatus 200 uses a plurality of PDSCHson each carrier element in the uplink, and thereby can transmit, in thesame subframe, a plurality of uplink transport blocks to the mobilestation apparatus 200. For example, the mobile station apparatus 200uses five PDSCHs on the UCC1, the UCC2, the UCC3, the UCC4 and the UCC5,and thereby can transmit, in the same subframe, uplink transport blocks(up to five at the maximum) to the base station apparatus 100.

Furthermore, in FIG. 4, the mobile station apparatus 200 can transmit,to the base station apparatus 100, the control information of HARQ for(a plurality of) PDCCHs and/or (a plurality of) downlink transportblocks transmitted from the base station apparatus 100. For example, themobile station apparatus 200 can transmit, to the base station apparatus100 in the same subframe, the control information of HARQ for fivePDCCHs and/or five downlink transport blocks transmitted from the basestation apparatus 100, using a plurality of PUCCHs (for example, fivePUCCHs, that is, PUCCHs indicated by oblique lines, grid lines, meshlines, vertical lines and horizontal lines). The mobile stationapparatus 200 also bundles or multiplexes the control information ofHARQ for the five PDCCHs and/or the five downlink transport blockstransmitted from the base station apparatus 100, and thereby cantransmit it to the base station apparatus 100 using single PUCCH (forexample, any one of the PUCCHs indicated by oblique lines, grid lines,mesh lines, vertical lines and horizontal lines).

Furthermore, the mobile station apparatus 200 partially bundles ormultiplexes the control information of HARQ for the five PDCCHs and/orthe five downlink transport blocks transmitted from the base stationapparatus 100, and thereby can also transmit it to the base stationapparatus 100. For example, the mobile station apparatus 200 partiallybundles or multiplexes the control information of HARQ for PDCCHs and/ordownlink transport blocks transmitted on the DCC1, the DCC2 and theDCC3. The mobile station apparatus 200 also partially bundles ormultiplexes the control information of HARQ for PDCCHs and/or downlinktransport blocks transmitted on the DCC4 and the DCC5. The mobilestation apparatus 200 can also transmit, to the base station apparatus100 in the same subframe, the control information of HARQ which has beenpartially bundled and multiplexed, using a plurality of PUCCHs (forexample, two PUCCHs, that is, the PUCCHs indicated by oblique lines andgrid lines).

Here, when the mobile station apparatus 200 bundles and transmits thecontrol information of HARQ to the base station apparatus 100, one pieceof control information of HARQ is calculated (generated) from thecontrol information of HARQ for (a plurality of) PDCCHs and/or (aplurality of) downlink transport blocks, and the calculated one piece ofcontrol information of HARQ is transmitted to the base station apparatus100. For example, the mobile station apparatus 200 calculates a logicalOR or a logical AND on information (a plurality of pieces of controlinformation of HARQ) indicating the DTX and/or the ACK/NACK for each of(the plurality of) PDCCHs and/or (the plurality of) downlink transportblocks, and can transmit the calculated control information (one pieceof control information of HARQ) to the base station apparatus 100. Forexample, the mobile station apparatus 200 calculates a logical OR or alogical AND from information indicating the DTX and/or the ACK/NACK foreach of PDCCHs and/or downlink transport blocks transmitted from thebase station apparatus 100 on the DCC1, the DCC2, the DCC3, the DCC4 andthe DCC5, and can transmit the calculated control information to thebase station apparatus 100.

When the mobile station apparatus 200 multiplexes and transmits thecontrol information of HARQ to the base station apparatus 100, themobile station apparatus 200 transmits, to the base station apparatus100, a plurality of pieces of control information expressing all thecombinations of the control information of HARQ for each of (a pluralityof) PDCCHs and/or (a plurality of) downlink transport blocks (notinformation necessary for expressing all the combinations but partialpieces of control information may be transmitted to the base stationapparatus 100). For example, the mobile station apparatus 200 expresses,with a plurality of bits, combinations of information indicating the DTXand/or the ACK/NACK for each of (the plurality of) PDCCHs and/or (theplurality of) downlink transport blocks, and thereby can transmit themto the base station apparatus 100. For example, the mobile stationapparatus 200 expresses, with a plurality of bits, combinations ofinformation indicating the DTX and/or the ACK/NACK for each of PDCCHsand/or downlink transport blocks transmitted from the base stationapparatus 100 on the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5,and thereby can transmit them to the base station apparatus 100.

In FIG. 4, the base station apparatus 100 can set (specify) an uplinkcarrier element for the transmission of the control information of HARQby the mobile station apparatus 200. For example, the base stationapparatus 100 can semi-statically set, with the RRC signaling, theuplink carrier element for the transmission of the control informationof HARQ by the mobile station apparatus 200. For example, the basestation apparatus 100 can semi-statically set, with the RRC signaling,the uplink carrier element, where the PUCCH is mapped, for thetransmission of the control information of HARQ by the mobile stationapparatus 200. FIG. 4 shows an example where, as the uplink carrierelement, where the PUCCH is mapped, for the transmission of the controlinformation of HARQ by the mobile station apparatus 200, the basestation apparatus 100 sets the UCC3. Here, as the uplink carrier elementfor the transmission of the control information of HARQ by the mobilestation apparatus 200, the base station apparatus 100 can also set aplurality of uplink carrier elements.

In FIG. 4, the base station apparatus 100 sets (allocates), to themobile station apparatus 200, the resources of (a plurality of) PUCCHsfor the transmission of the control information of HARQ for (a pluralityof) PDCCHs and/or (a plurality of) downlink transport blocks by themobile station apparatus 200. In the following description of thepresent embodiment, for ease of the description, the PUCCH that issemi-statically set (allocated) by the base station apparatus 100 to themobile station apparatus 200 is described as a first PUCCH, and thePUCCH that is dynamically set (allocated) by the base station apparatus100 to the mobile station apparatus 200 is described as a second PUCCH.FIG. 4 shows that the base station apparatus 100 semi-statically setsthe first PUCCHs (the PUCCHs indicated by grid lines, mesh lines,vertical lines and horizontal lines) to the mobile station apparatus200, and dynamically sets the second PUCCH (the PUCCH indicated byoblique lines) to the mobile station apparatus 200 in the same subframeas the subframe in which the first PUCCHs are set.

In other words, for example, the base station apparatus 100 uses the RRCsignaling, and thereby can set (allocate) the first PUCCHs (the PUCCHsindicated by grid lines, mesh lines, vertical lines and horizontallines) to the mobile station apparatus 200. Here, the base stationapparatus 100 links (corresponds) each of downlink carrier elements toeach of resources of the first PUCCHs, and thereby can set them to themobile station apparatus 200. FIG. 4 shows that the base stationapparatus 100 links the DCC1 to the first PUCCH indicated by grid lines,the DCC2 to the first PUCCH indicated by mesh lines, the DCC4 to thefirst PUCCH indicated by vertical lines and the DCC5 to the first PUCCHindicated by horizontal lines, and sets the each of first PUCCHs to themobile station apparatus 200. In other words, the base station apparatus100 can semi-statically set (allocate) a set of first PUCCHs for thetransmission of the control information of HARQ by the mobile stationapparatus 200. Although, here, in FIG. 4, the base station apparatus 100sets a set of four first PUCCHs to the mobile station apparatus 200, thebase station apparatus 100 may set, as the set of first PUCCHs, anynumber of sets (the size (number) of first PUCCHs can be set). Forexample, the base station apparatus 100 can change the set (number) offirst PUCCHs according to the ability of the mobile station apparatus200 within a cell or the number of carrier elements when communicationwith the mobile station apparatus 200 is performed. For example, thebase station apparatus 100 can set two first PUCCHs to the mobilestation apparatus 200 when communication with the mobile stationapparatus 200 is performed using three downlink carrier elements. Thebase station apparatus 100 can semi-statically set the first PUCCHssettable (where the size (number) of sets can be changed) for the mobilestation apparatus 200.

Also, the base station apparatus 100 links (corresponds) PDSCHstransmitted on each of downlink carrier elements to each of resources ofthe first PUCCHs, and thereby can set them to the mobile stationapparatus 200. For example, FIG. 4 shows that the base station apparatus100 links the PDSCH transmitted on the DCC1 to the first PUCCH indicatedby grid lines, the PDSCH transmitted on the DCC2 to the first PUCCHindicated by mesh lines, the PDSCH transmitted on the DCC4 to the firstPUCCH indicated by vertical lines and the PDSCH transmitted on the DCC5to the first PUCCH indicated by horizontal lines, and sets the each offirst PUCCHs to the mobile station apparatus 200. Although, here, inFIG. 4, the base station apparatus 100 sets a set of four first PUCCHsto the mobile station apparatus 200, the base station apparatus 100 mayset, as the set of first PUCCHs, any number of sets (the size (number)of first PUCCHs can be set).

Furthermore, for example, the base station apparatus 100 associates thesecond PUCCH which is used for transmitting the control information ofHARQ (the PUCCH indicated by oblique lines) with the PDCCH which is usedfor assigning the PDSCH, and can dynamically set (allocate) it to themobile station apparatus 200. For example, the base station apparatus100 associates the second PUCCH with the position of the PDCCH (thePDCCH indicated by oblique lines) in a PDCCH resource region (PDCCHresource), the PDCCH is set on the downlink carrier element, and candynamically set second PUCCH to the mobile station apparatus 200. Inother words, the base station apparatus 100 associates the second PUCCHwith on which the position of the PDCCH is set, in the PDCCH resource,and can instruct the mobile station apparatus 200 to transmit thecontrol information of HARQ using the second PUCCH allocated in whichposition of the PUCCH resource region (PUCCH resource). Here, the PUCCHresource region can be set cell-specifically, for example, the basestation apparatus 100, using the broadcast channel (broadcastinformation). The PUCCH resource region can also be set the mobilestation apparatus-specifically, for example, the base station apparatus100, using the RRC signaling.

In other words, the mobile station apparatus 200 maps, according to howthe PDCCH is set in the PDCCH region, the control information of HARQ onthe second PUCCH in the PUCCH region, and can transmit it to the basestation apparatus 100. Here, the correspondence between the PDCCH set onthe downlink carrier element and the second PUCCH set on the uplinkcarrier element is specified by, for example, making the first CCE indexof the CCEs constituting the PDCCH correspond with the index of thesecond PUCCH (FIG. 4 shows that the first CCE index of the CCEsconstituting the PDCCH indicated by oblique lines with the index of thesecond PUCCH indicated by oblique lines).

Moreover, the base station apparatus 100 can cell-specifically set thelinking (correspondence) between each of the downlink carrier elementswhere the PDCCH is set and one uplink carrier element where the secondPUCCH is set, using the broadcast information (broadcast channel).Furthermore, the base station apparatus 100 can the mobile stationapparatus-specifically set the linking (correspondence) between each ofthe downlink carrier elements where the PDCCH is set and one uplinkcarrier element where the second PUCCH is set, using the RRC signaling.FIG. 4 shows that the base station apparatus 100 uses the broadcastinformation or the RRC signaling, and thereby links the DCC3 and theUCC3. For example, in FIG. 4, when the base station apparatus 100 linksthe DCC2 and the UCC3, the base station apparatus 100 associates thesecond PUCCH with the position of the PDCCH in the PDCCH resourceregion, the PDCCH is set on the DCC2, and sets the second PUCCH on theUCC3.

In other words, the second PUCCH dynamically set by the base stationapparatus 100 is associated only between the downlink carrier elementand the uplink carrier element linked by the broadcast information orthe RRC signaling. Although, here, in FIG. 4, the base station apparatus100 links only one downlink carrier element (DCC3) and one uplinkcarrier element (UCC3), the base station apparatus 100 can also link aplurality of downlink carrier elements and a plurality of uplink carrierelements. For example, in FIG. 4, the base station apparatus 100 canlink the DCC2 and the UCC2, and link the DCC3 and the UCC4. In thiscase, the PDCCH set on the downlink carrier element and the second PUCCHset on the uplink carrier element are associated only between thedownlink carrier element and the uplink carrier element linked together(the DCC2 and the UCC2, and the DCC3 and the UCC4).

In FIG. 4, the base station apparatus 100 uses the RRC signaling, andthereby semi-statically sets (allocates) the first PUCCHs (the PUCCHsindicated by grid lines, mesh lines, vertical lines and horizontallines) to the mobile station apparatus 200, and dynamically sets thesecond PUCCH (the PUCCH indicated by oblique lines) to the mobilestation apparatus 200 in the same subframe as the subframe in which thefirst PUCCH is allocated. As described above, the mobile stationapparatus 200 transmits, to the base station apparatus 100, the controlinformation of HARQ for (a plurality of) PDCCHs and/or (a plurality of)downlink transport blocks, using a plurality of PUCCHs or single PUCCH.In other words, the mobile station apparatus 200 uses the first PUCCHand the second PUCCH set by the base station apparatus 100, and therebycan transmit the control information of HARQ to the base stationapparatus 100. The mobile station apparatus 200 also uses the firstPUCCH or the second PUCCH allocated by the base station apparatus 100,and thereby can transmit the control information of HARQ to the basestation apparatus 100. In this case, the mobile station apparatus 200bundles the control information of HARQ, and can transmit it to the basestation apparatus 100. The mobile station apparatus 200 also multiplexesthe control information of HARQ, and can transmit it to the base stationapparatus 100.

The first PUCCH that is semi-statically set by the base stationapparatus 100 to the mobile station apparatus 200 will be described. InFIG. 4, the base station apparatus 100 can apply group scheduling to thefirst PUCCHs (the PUCCHs indicated by grid lines, mesh lines, verticallines and horizontal lines) semi-statically allocated using the RRCsignaling. In other words, the base station apparatus 100 can set thefirst PUCCHs for a plurality of mobile station apparatuses 200, and canmake the first PUCCHs shared by the mobile station apparatuses 200. FIG.4 shows that the base station apparatus 100 applies the group schedulingto the first PUCCHs indicated by grid lines, mesh lines, vertical linesand horizontal lines, and that the first PUCCHs are individually sharedby the mobile station apparatuses 200. FIG. 4 shows that the secondPUCCH dynamically set by the base station apparatus 100 is dynamicallyscheduled for a certain mobile station apparatus 200 (dynamic schedulingis applied).

Likewise, FIG. 5 is a diagram showing another example of the mobilecommunication system to which the first embodiment is applicable. FIG. 5shows that a frequency band having a bandwidth of 100 MHz and used inthe downlink communication is composed of five downlink carrier elements(DCC1, DCC2, DCC3, DCC4 and DCC5), each having a bandwidth of 20 MHz.FIG. 5 also shows that a frequency band having a bandwidth of 100 MHzand used in the uplink communication is composed of five uplink carrierelements (UCC1, UCC2, UCC3, UCC4 and UCC5), each having a bandwidth of20 MHz.

FIG. 5 differs from FIG. 4 in that the base station apparatus 100 uses aplurality of PDCCHs (the PDCCHs indicated by oblique lines and meshlines) on one downlink carrier element (DCC3), and sets (allocates) aplurality of PDSCHs. As described above, the base station apparatus 100transmits the component carrier identifier information on each of thePDCCHs in the one downlink carrier element, and thereby can set(allocate) the same downlink carrier element as the downlink carrierelement transmitting the PDCCH or the PDSCHs allocated in differentdownlink carrier elements. FIG. 5 shows an example where the basestation apparatus 100 transmits a plurality of PDCCHs (the PDCCHsindicated by oblique lines and mesh lines) on the DCC3 and sets thePDSCH of each of the DCC3 and the DCC4.

In FIG. 5, the base station apparatus 100 sets (allocates) the resourcesof (a plurality of) PUCCHs for the transmission of the controlinformation of HARQ for (a plurality of) PDCCHs and/or (a plurality of)downlink transport blocks by the mobile station apparatus 200. FIG. 5shows that the base station apparatus 100 semi-statically sets the firstPUCCHs (the PUCCHs indicated by grid lines, vertical lines andhorizontal lines) to the mobile station apparatus 200, and dynamicallysets the second PUCCH (the PUCCHs indicated by oblique lines and meshlines) to the mobile station apparatus 200 in the same subframe as thesubframe in which the first PUCCH are set.

In other words, in FIG. 5, the base station apparatus 100 uses the RRCsignaling, and thereby can semi-statically set the first PUCCHs (thePUCCHs indicated by grid lines, vertical lines and horizontal lines) tothe mobile station apparatus 200. Here, the base station apparatus 100links (corresponds) each of downlink carrier elements to each ofresources of the first PUCCHs, and thereby can set them to the mobilestation apparatus 200. FIG. 5 shows an example where the base stationapparatus 100 links the DCC1 to the first PUCCH indicated by grid lines,the DCC2 to the first PUCCH indicated by vertical lines and the DCC5 tothe first PUCCH indicated by horizontal lines, and sets each of firstPUCCHs to the mobile station apparatus 200. Here, as described above,the base station apparatus 100 semi-statically can set (allocate) a setof first PUCCHs for the transmission of the control information of HARQby the mobile station apparatus 200. Although, in FIG. 5, the basestation apparatus 100 sets a set of three first PUCCHs to the mobilestation apparatus 200, the base station apparatus 100 may set, as theset of first PUCCHs, any number of sets (the size (number) of the setsof the first PUCCHs can be set). The base station apparatus 100 cansemi-statically set the first PUCCHs settable (where the size (number)of sets can be changed) to the mobile station apparatus 200.

The base station apparatus 100 associates the second PUCCH (the PUCCHsindicated by oblique lines and mesh lines) with the PDCCH, and candynamically set (allocate) it to the mobile station apparatus 200. Inother words, the base station apparatus 100 can set, with each of aplurality of PDCCHs (the PDCCHs indicated by oblique lines and meshlines) transmitted on the DCC3, a plurality of second PUCCH (the PUCCHsindicated by oblique lines and mesh lines) allocated on the DCC3. FIG. 5shows that the base station apparatus 100 associates the second PUCCHindicated by oblique lines with the PDCCH indicated by oblique lines,and dynamically sets the second PUCCH to the mobile station apparatus200, and that the base station apparatus 100 associates the second PUCCHindicated by mesh lines with the PDCCH indicated by mesh lines, anddynamically sets the second PUCCH to the mobile station apparatus 200.

Here, the base station apparatus 100 uses the broadcast information orthe RRC signaling, and thereby links (makes a correspondence between)the downlink carrier element where the PDCCH is set and the uplinkcarrier element where the second PUCCH is set. Specifically, in FIG. 5the base station apparatus 100 links the DCC3 and the UCC3, associates aplurality of second PUCCHs (the PUCCHs indicated by oblique lines andmesh lines) set on the UCC3 with the position of each of a plurality ofPDCCHs (the PDCCHs indicated by oblique lines and mesh lines) in thePDCCH region, the each of a plurality of PDCCHs are allocated on theDCC3, and can set each of the second PUCCHs. In other words, in one ofthe downlink carrier elements and one of the uplink carrier elementslinked by the broadcast information or the RRC signaling from the basestation apparatus 100, a plurality of PDCCHs which is used for assigningthe a plurality of PDSCHs and a plurality of PUCCHs which is used fortransmitting the control information of HARQ are dynamically associatedwith each other.

As described above, the mobile station apparatus 200 transmits, to thebase station apparatus 100, the control information of HARQ for (aplurality of) PDCCHs and/or (a plurality of) downlink transport blocks,using a plurality of PUCCHs or single PUCCH. In other words, the mobilestation apparatus 200 uses the first PUCCH and the second PUCCHallocated by the base station apparatus 100, and thereby can transmitthe control information of HARQ to the base station apparatus 100. Themobile station apparatus 200 also uses the first PUCCH or the secondPUCCH allocated by the base station apparatus 100, and thereby cantransmit the control information of HARQ to the base station apparatus100. In this case, the mobile station apparatus 200 bundles the controlinformation of HARQ, and transmits it to the base station apparatus 100.The mobile station apparatus 200 also multiplexes the controlinformation of HARQ, and transmits it to the base station apparatus 100.

As in the description of FIG. 4, in FIG. 5, the base station apparatus100 can apply the group scheduling to the first PUCCHs (the PUCCHsindicated by grid lines, vertical lines and horizontal lines)semi-statically allocated using the RRC signaling. In other words, thebase station apparatus 100 can set the first PUCCHs for a plurality ofmobile station apparatuses 200, and can make the first PUCCHs shared bythe mobile station apparatuses 200. FIG. 5 shows that the base stationapparatus 100 applies the group scheduling to the first PUCCHs indicatedby grid lines, vertical lines and horizontal lines, and that the firstPUCCHs are individually shared by the mobile station apparatuses 200.FIG. 5 shows that the second PUCCHs (the PUCCHs indicated by obliquelines and mesh lines) dynamically set by the base station apparatus 100is dynamically scheduled for a certain mobile station apparatus 200 (thedynamic scheduling is applied).

As described above, in the first embodiment, since the mobile stationapparatus 200 transmits the control information of HARQ, the basestation apparatus 100 semi-statically can set the first PUCCH to themobile station apparatus 200, and dynamically set the second PUCCH tothe mobile station apparatus 200 in the same subframe as the subframe inwhich the first PUCCH is allocated. The mobile station apparatus 200also uses the first PUCCH and/or the second PUCCH set by the basestation apparatus 100, and thereby can transmit the control informationof HARQ to the base station apparatus 100. In this case, the mobilestation apparatus 200 bundles the control information of HARQ, andtransmits it to the base station apparatus 100. The mobile stationapparatus 200 also multiplexes the control information of HARQ, andtransmits it to the base station apparatus 100.

The base station apparatus 100 and the mobile station apparatus 200transmit and receive the control information of HARQ as described above,and thus the base station apparatus 100 can semi-statically set thefirst PUCCH for each of the mobile station apparatuses 200, and the basestation apparatus 100 can change (modify) the (number of) first PUCCHsthat are set for each of the mobile station apparatuses 200 accordingto, for example, the number of carrier elements used in thecommunication and the conditions of radio resources within the cell. Thebase station apparatus 100 changes (modifies) the first PUCCHs that aresemi-statically allocated for each of the mobile station apparatuses200, and thus it is possible to effectively allocate the resources ofthe uplink and to effectively use the radio resources.

The base station apparatus 100 applies the group scheduling when setsthe first PUCCH, and thus, even if the mobile station apparatus 200 doesnot use the first PUCCH (for example, the mobile station apparatus 200uses only one downlink/uplink carrier element to communicate with thebase station apparatus 100), it is possible to set the first PUCCH forother mobile station apparatuses and effectively use the resources ofthe uplink. Furthermore, the base station apparatus 100 associates thesecond PUCCH allocated on the carrier element of the uplink with theposition of the PDCCH allocated in the carrier element of the downlink,and dynamically sets the second PUCCH, and thus it is possible toeffectively set the second PUCCH for the mobile station apparatus 200.

The mobile station apparatus 200 bundles or multiplexes the controlinformation of HARQ and transmits it to the base station apparatus 100,and thus it is possible to reduce transmit power in the mobile stationapparatus 200 and transmit the control information of HARQ. The mobilestation apparatus 200 uses any one of (a small number of) (a pluralityof) PUCCHs set by the base station apparatus 100, and transmits thecontrol information of HARQ, and thus it is possible to transmit thecontrol information of HARQ while reducing the transmit power in themobile station apparatus 200.

In other words, when the base station apparatus 100 and the mobilestation apparatus 200 use a broadband frequency band of a plurality ofcarrier elements to perform communication, it is possible to effectivelytransmit and receive the control information of HARQ with considerationgiven to the method of setting the resource by the base stationapparatus 100 and the transmit power in the mobile station apparatus200. Here, although, in the first embodiment, the example of theoperation of the base station apparatus 100 and the mobile stationapparatus 200 in the mobile communication system that has been subjectedto symmetric frequency band aggregation, it is naturally possible toapply the same method to the mobile communication system that has beensubjected to the asymmetric frequency band aggregation.

Second Embodiment

The second embodiment of the present invention will now be described. Inthe second embodiment, the base station apparatus 100 semi-staticallysets the first PUCCH to the mobile station apparatus 200, transmits, tothe mobile station apparatus 200, information indicating activationand/or deactivation for the downlink component carrier and dynamicallysets the second PUCCH to the mobile station apparatus 200 in the samesubframe as the subframe in which the first PUCCH is allocated whereasthe mobile station apparatus 200 uses the first PUCCH and/or the secondPUCCH activated according to the information indicating the activationand/or the deactivation, and thereby can transmit the controlinformation of HARQ to the base station apparatus 100. Moreover, thebase station apparatus 100 semi-statically sets the first PUCCH to themobile station apparatus 200, transmits, to the mobile station apparatus200, information indicating the activation and/or the deactivation forthe downlink component carrier and dynamically sets the second PUCCH tothe mobile station apparatus 200 in the same subframe as the subframe inwhich the first PUCCH is allocated whereas the mobile station apparatus200 uses the first PUCCH and/or the second PUCCH selected according tothe information indicating the activation and/or the deactivation, andthereby can transmit the control information of HARQ to the base stationapparatus 100. In this case, the mobile station apparatus 200 can bundlethe control information of HARQ, and transmit to the base stationapparatus 100. The mobile station apparatus 200 can also multiplex thecontrol information of HARQ, and transmit it to the base stationapparatus 100. In the second embodiment, the same operations of the basestation apparatus 100 and the mobile station apparatus 200 shown in thefirst embodiment are applied.

FIG. 6 is a diagram illustrating an example of the second embodiment. Onthe left side of FIG. 6, in a horizontal direction, it is shown that afrequency band having a bandwidth of 100 MHz and used in thecommunication of the downlink is composed of five downlink carrierelements (DCC1, DCC2, DCC3, DCC4 and DCC5). In a vertical direction,time (subframe) is shown; as an example, a downlink subframe #n, adownlink subframe #n+m, a downlink subframe #n+p and a downlink subframe#n+q are conceptually shown (the downlink subframe is hereinafterreferred to as a subframe). On the right side of FIG. 6, the processingflow of the base station apparatus 100 and the mobile station apparatus200 corresponding to the diagram on the left side is conceptually shown.

In FIG. 6, the base station apparatus 100 can set, for the mobilestation apparatus 200, a set of downlink carrier elements that might bescheduled for the mobile station apparatus 200 to receive the PDSCH inthe downlink. In the following description of the present embodiment,the set of carrier elements in the downlink is referred to a downlinkcarrier element set (DCC set: downlink component carrier set). Forexample, the base station apparatus 100 transmits, to the mobile stationapparatus 200, the RRC signaling including information for adding and/orremoving the downlink carrier elements, and can semi-statically set theDCC set (add and/or remove the downlink carrier elements). In otherwords, the base station apparatus 100 can set the DCC set for each ofthe mobile station apparatus 200 according to the conditions of radioresources within a cell to be controlled, the ability of each of themobile station apparatuses 200 and the conditions of the transmissionpath of each of the mobile station apparatuses 200.

In FIG. 6, the subframe #n, the subframe #n+m, the subframe #n+p and thesubframe #n+q indicate subframes in which the five downlink carrierelements (the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5) are setas the DCC set. Although, in FIG. 6, as an example, the base stationapparatus 100 sets the five downlink carrier elements as the DCC set,the base station apparatus 100 may set any number of downlink carrierelements as the DCC set.

Furthermore, in FIG. 6, the base station apparatus 100 transmits, to themobile station apparatus 200, the information on the activation and/orthe deactivation for the downlink carrier elements (the informationindicating the activation and/or the deactivation), and can activateand/or deactivate the set of downlink carrier elements (which may be aset of downlink carrier elements that might be scheduled for receivingthe PDSCH in the downlink). In the following description of the presentembodiment, this set of carrier elements in the downlink is referred toa downlink carrier element activation set (DCC active set: downlinkcomponent carrier active set). Here, the DCC active set is set for thedownlink carrier elements among the DCC set described above. The basestation apparatus 100 can also set the DCC active set as the downlinkcarrier elements in which the mobile station apparatus 200 attempts todetect the PDCCH (to monitor the PDCCH).

In FIG. 6, the subframe #n indicates a subframe in which five downlinkcarrier elements (the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5indicated by being colored in white) are not activated (deactivated).The subframe #n+m indicates a subframe in which four downlink carrierelements (the DCC1, the DCC2, the DCC3 and the DCC5 indicated by meshlines) are activated. Here, the subframe #n+m can be recognized to be asubframe in which, for the subframe #n, the DCC1, the DCC2, the DCC3 andthe DCC5 are activated and the deactivation for the DCC4 is maintained.The subframe #n+P indicates a subframe in which three downlink carrierelements (the DCC1, the DCC3 and the DCC5 indicated by mesh lines) areactivated. Here, the subframe #n+p can be recognized to be a subframe inwhich, for the subframe #n+m, the activation for the DCC1 and the DCC3is maintained, the DCC2 and the DCC5 are deactivated and the DCC4 isactivated. The subframe #n+q indicates a subframe in which five downlinkcarrier elements (the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5indicated by being colored in white) are deactivated (not activated).Here, the subframe #n+q can be recognized to be a subframe in which, forthe subframe #n+p, the DCC1, the DCC3 and the DCC4 are deactivated andthe deactivation for the DCC2 and DCC5 is maintained.

For example, the base station apparatus 100 transmits the information onthe activation and/or the deactivation for the downlink carrier elements(the information indicating the activation and/or the deactivation) onthe PDCCH, and can dynamically control (set, indicate) the DCC activeset. Here, the base station apparatus 100 uses the PDCCH, and therebycan control the activation for the downlink carrier elements. The basestation apparatus 100 also uses the PDCCH, and thereby can control thedeactivation for the downlink carrier elements. Furthermore, the basestation apparatus 100 uses the PDCCH, and thereby can control theactivation and the deactivation for the downlink carrier elements in thesame subframe (at the same timing). As described above, the base stationapparatus 100 sets the DCC active set for the mobile station apparatus200, and thus it is possible to save power consumption in the mobilestation apparatus 200 (to reduce the number of DCCs where the PDCCH tobe monitored by the mobile station apparatus 200 is allocated), and toachieve power saving in the mobile station apparatus 200.

Although, here, in the following description, the base station apparatus100 uses the PDCCH to control the DCC active set, the base stationapparatus 100 can use the RRC signaling and a MAC control element (theMAC signaling) and control the DCC active set. For example, the basestation apparatus 100 may control the DCC active set by associating theDCC active set with discontiguous reception (DRX) in which control isperformed using the MAC control element. The base station apparatus 100uses the PDCCH to control the DCC active set, and thus it is possible tomore dynamically (for example, at intervals of 1 ms) control the DCCactive set, and to most enhance the effects on the power saving of themobile station apparatus 200. On the other hand, the base stationapparatus 100 uses the RRC signaling or the MAC control element tocontrol the DCC active set, and thus it is possible to more reliablycontrol the DCC active set.

The processing flow of the base station apparatus 100 and the mobilestation apparatus 200 on the right side of FIG. 6 will be described.Before the subframe #n of FIG. 6, the base station apparatus 100 setsthe five downlink carrier elements (the DCC1, the DCC2, the DCC3, theDCC4 and the DCC5) as the DCC set to the mobile station apparatus 200(step S1). Before the subframe #n, in order for the mobile stationapparatus 200 to transmit the control information of HARQ, the basestation apparatus 100 notifies (transmits), to the mobile stationapparatus 200, setting information (parameter) for semi-staticallysetting (a plurality of) first PUCCHs using the RRC signaling. Forexample, in order for the mobile station apparatus 200 to transmit thecontrol information of HARQ, the base station apparatus 100 can notify,to the mobile station apparatus 200, information on four resources ofthe first PUCCHs using the RRC signaling.

In FIG. 6, for example, the base station apparatus 100 can notify, tothe mobile station apparatus 200, setting information on the PUCCHslinked to each of the DCC1, the DCC2, the DCC4 and the DCC5 as thesetting information of the first PUCCHs. Moreover, for example, the basestation apparatus 100 can set the linking between the DCC3 and oneuplink carrier element. In other words, the PUCCH set on one uplinkcarrier element linked to the DCC3 is associated, as the second PUCCH,with the PDCCH transmitted on the DCC3.

The subframe #n indicates a subframe in which the five downlink carrierelements (the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5) set bythe base station apparatus 100 as the DCC set are not activated. Inother words, the subframe #n indicates a subframe in which the basestation apparatus 100 does not set the DCC active set for the mobilestation apparatus 200. In the subframe #n, the mobile station apparatus200 releases the resources of the first PUCCHs in which the base stationapparatus 100 notifies the setting information. Specifically, the mobilestation apparatus 200 releases the resources of the first PUCCH linkedto each of the DCC1, the DCC2, the DCC4 and the DCC5.

Between the subframe #n and the subframe #n+m. the base stationapparatus 100 sets the four downlink carrier elements (the DCC1, theDCC2, the DCC3 and the DCC5) to the mobile station apparatus 200 as theDCC active set (step S2). In other words, the deactivation for the DCC 4is maintained. Here, the mobile station apparatus 200 can activate theresources of the first PUCCHs according to the DCC active set that isset by the base station apparatus 100. Specifically, the mobile stationapparatus 200 can activate, according to the DCC active set, theresources of the first PUCCH linked to each of the DCC1, the DCC2, andthe DCC5. In other words, the resources of the first PUCCH linked to theDCC4 maintain the release (the mobile station apparatus 200 can maintainthe release of the resources of the first PUCCH linked to the DCC4.Specifically, according to the DCC active set that is set by the basestation apparatus 100, based on the setting information on the firstPUCCHs notified by the base station apparatus 100, three first PUCCHsare semi-statically set (allocated) for the mobile station apparatus200.

In the subframe #n+m, the base station apparatus 100 uses (a pluralityof) PDCCHs to set (allocate) (a plurality of) PDSCHs to the mobilestation apparatus 200 (step S3). The base station apparatus 100 alsouses (a plurality of) PDSCHs to transmit, to the mobile stationapparatus 200, (a plurality of) downlink transport blocks in the samesubframe. For example, the base station apparatus 100 transmits thePDCCH on each of the four downlink carrier elements (the DCC1, the DCC2,the DCC3 and the DCC5) and sets four PDSCHs. The base station apparatus100 also uses the four PDSCHs, and transmits, to the mobile stationapparatus 200, the four downlink transport blocks in the same subframe.The base station apparatus 100 associates the second PUCCH with thePDCCH transmitted on the DCC3, and dynamically sets (allocates) thesecond PUCCH to the mobile station apparatus 200. In other words, thebase station apparatus 100 sets the DCC active set, and therebydynamically sets the second PUCCH to the mobile station apparatus 200 inthe same subframe as (a plurality of) first PUCCHs semi-statically set.

In the uplink subframe corresponding to the subframe #n+m, the mobilestation apparatus 200 transmits the control information of HARQ for (aplurality of) PDCCHs and/or (a plurality of) downlink transport blocksto the base station apparatus 100 (step S4). In other words, the mobilestation apparatus 200 uses the three first PUCCHs activated (added,maintained) according to the DCC active set and/or the second PUCCHdynamically allocated, and thereby can transmit the control informationof HARQ to the base station apparatus 100. In this case, the mobilestation apparatus 200 bundles the control information of HARQ, and cantransmit it to the base station apparatus 100. The mobile stationapparatus 200 also multiplexes the control information of HARQ, and cantransmit it to the base station apparatus 100.

Between the subframe #n+m and the subframe #n+p, the base stationapparatus 100 sets the three downlink carrier elements (the DCC1, theDCC3 and the DCC4) to the mobile station apparatus 200 as the DCC activeset (step S5). In other words, the base station apparatus 100deactivates the two downlink carrier elements (the DCC2 and the DCC5).Here, the mobile station apparatus 200 can activate and release,according to the DCC active set by the base station apparatus 100, theresources of the first PUCCH. In other words, the mobile stationapparatus 200 can activate, according to the DCC active set, theresources of the first PUCCHs linked to the DCC1 and the DCC4 (canmaintain the activation for the resources of the first PUCCHs linked tothe DCC1, and add the activation for the resources of the first PUCCHslinked to the DCC4). The mobile station apparatus 200 can also releasethe resources of the first PUCCHs linked to the DCC2 and the DCC5.Specifically, according to the DCC active set that is set by the basestation apparatus 100, based on the setting information on the firstPUCCHs notified by the base station apparatus 100, two first PUCCHs aresemi-statically set (allocated) for the mobile station apparatus 200.

In the subframe #n+p, the base station apparatus 100 uses (a pluralityof) PDCCHs to set (a plurality of) PDSCHs to the mobile stationapparatus 200 (step S6). The base station apparatus 100 also uses (aplurality of) PDSCHs to transmit, to the mobile station apparatus 200,(a plurality of) downlink transport blocks in the same subframe. Forexample, the base station apparatus 100 transmits the PDCCH on each ofthe three activated downlink carrier elements (the DCC1, the DCC3 andthe DCC4) and sets three PDSCHs. The base station apparatus 100 alsouses the three PDSCHs, and transmits, to the mobile station apparatus200, the three downlink transport blocks using the three PDSCHs.Furthermore, the base station apparatus 100 associates the second PUCCHwith the PDCCH transmitted on the DCC3, and dynamically sets the secondPUCCH to the mobile station apparatus 200.

In the uplink subframe corresponding to the subframe #n+p, the mobilestation apparatus 200 transmits the control information of HARQ for (aplurality of) PDCCHs and/or (a plurality of) downlink transport blocksto the base station apparatus 100 (step S7). In other words, the mobilestation apparatus 200 uses the two first PUCCHs activated (added,maintained) according to the DCC active set and/or the second PUCCHdynamically allocated, and thereby can transmit the control informationof HARQ to the base station apparatus 100. In this case, the mobilestation apparatus 200 bundles the control information of HARQ, and cantransmit it to the base station apparatus 100. The mobile stationapparatus 200 also multiplexes the control information of HARQ, and cantransmit it to the base station apparatus 100.

Between the subframe #n+p and the subframe #n+q, the base stationapparatus 100 deactivates the five downlink carrier elements (the DCC1,the DCC2, the DCC3, the DCC4 and the DCC5) (step S8). Here, the mobilestation apparatus 200 can release the resources of the first PUCCHaccording to the DCC active set by the base station apparatus 100. Inother words, the mobile station apparatus 200 releases, according to theDCC active set, the resources of the first PUCCHs linked to the DCC1,the DCC2, the DCC3, the DCC4 and the DCC5 (can release the resources ofthe first PUCCHs linked to the DCC1, the DCC3 and the DCC5, and canmaintain the release of the resources of the first PUCCHs linked to theDCC2 and the DCC5).

Another example of the processing flow of the base station apparatus 100and the mobile station apparatus 200 in FIG. 6 will be furtherdescribed. As described above, before the subframe #n of FIG. 6, thebase station apparatus 100 sets the five downlink carrier elements (theDCC1, the DCC2, the DCC3, the DCC4 and the DCC5) as the DCC set to themobile station apparatus 200 (step S1). Before the subframe #n, the basestation apparatus 100 uses the RRC signaling to semi-statically set(allocate) (a plurality of) first PUCCHs for the transmission of thecontrol information of HARQ by the mobile station apparatus 200. Forexample, in FIG. 6, the base station apparatus 100 can set the fourfirst PUCCHs linked to the DCC1, the DCC2, the DCC4 and the DCC5 to themobile station apparatus 100. For example, the base station apparatus100 sets the linking between the DCC3 and one uplink carrier element. Inother words, the PUCCH set on the one uplink carrier element linked tothe DCC3 is associated, as the second PUCCH, with the PDCCH transmittedon the DCC3.

The subframe #n indicates a subframe in which the five downlink carrierelements (the DCC1, the DCC2, the DCC3, the DCC4 and the DCC5) set bythe base station apparatus 100 as the DCC set are not activated. Inother words, the subframe #n indicates a subframe in which the basestation apparatus 100 does not set the DCC active set for the mobilestation apparatus 200. Here, the four first PUCCHs linked to the DCC1,the DCC2, the DCC4 and the DCC5 are set (allocated) to the mobilestation apparatus 200.

Between the subframe #n and the subframe #n+m. the base stationapparatus 100 sets the four downlink carrier elements (the DCC1, theDCC2, the DCC3 and the DCC5) to the mobile station apparatus 200 as theDCC active set (step S2). In other words, the deactivation for the DCC4is maintained. Here, the mobile station apparatus 200 can select(modify) the resources of the first PUCCHs for the transmission of thecontrol information of HARQ according to the DCC active set that is setby the base station apparatus 100. Specifically, the mobile stationapparatus 200 can select (modify), according to the DCC active set, theresources of the first PUCCHs linked to the DCC1, the DCC2, and the DCC5as the resources of the first PUCCHs for the transmission of the controlinformation of HARQ. Here, the resources of the first PUCCHs linked tothe DCC4 are kept set (allocated) to the mobile station apparatus 200.

In the subframe #n+m, the base station apparatus 100 uses (a pluralityof) PDCCHs to set (allocate) (a plurality of) PDSCHs to the mobilestation apparatus 200 (step S3). The base station apparatus 100 alsouses (a plurality of) PDSCHs to transmit, to the mobile stationapparatus 200, (a plurality of) downlink transport blocks in the samesubframe. For example, the base station apparatus 100 transmits thePDCCH on each of the four downlink carrier elements (the DCC1, the DCC2,the DCC3 and the DCC5) and sets four PDSCHs. The base station apparatus100 also uses the four PDSCHs, and transmits, to the mobile stationapparatus 200, the four downlink transport blocks in the same subframe.The base station apparatus 100 associates the second PUCCH with thePDCCH transmitted on the DCC3, and dynamically sets (allocates) thesecond PUCCH to the mobile station apparatus 200. In other words, thebase station apparatus 100 sets the DCC active set, and therebydynamically sets the second PUCCH to the mobile station apparatus 200 inthe same subframe as (a plurality of) first PUCCHs semi-statically set.

In the uplink subframe corresponding to the subframe #n+m, the mobilestation apparatus 200 transmits the control information of HARQ for (aplurality of) PDCCHs and/or (a plurality of) downlink transport blocksto the base station apparatus 100 (step S4). In other words, the mobilestation apparatus 200 uses the three first PUCCHs selected (modified)according to the DCC active set and/or the second PUCCH dynamicallyallocated, and thereby can transmit the control information of HARQ tothe base station apparatus 100. In this case, the mobile stationapparatus 200 bundles the control information of HARQ, and can transmitit to the base station apparatus 100. The mobile station apparatus 200also multiplexes the control information of HARQ, and can transmit it tothe base station apparatus 100.

Between the subframe #n+m and the subframe #n+p, the base stationapparatus 100 sets the three downlink carrier elements (the DCC1, theDCC3 and the DCC4) to the mobile station apparatus 200 as the DCC activeset (step S5). In other words, the base station apparatus 100deactivates the two downlink carrier elements (the DCC2 and the DCC5).Here, the mobile station apparatus 200 can select (modify), according tothe DCC active set by the base station apparatus 100, the resources ofthe first PUCCH for the transmission of the control information of HARQ.In other words, the mobile station apparatus 200 can select (modify),according to the DCC active set, the resources of the first PUCCHslinked to the DCC1 and the DCC4 as the resources of the first PUCCHs forthe transmission of the control information of HARQ. Here, the resourcesof the first PUCCHs linked to the DCC2 and the DCC5 are kept set(allocated) to the mobile station apparatus 200.

In the subframe #n+p, the base station apparatus 100 uses (a pluralityof) PDCCHs to set (a plurality of) PDSCHs to the mobile stationapparatus 200 (step S6). The base station apparatus 100 also uses (aplurality of) PDSCHs to transmit, to the mobile station apparatus 200,(a plurality of) downlink transport blocks in the same subframe. Forexample, the base station apparatus 100 transmits the PDCCH on each ofthe three activated downlink carrier elements (the DCC1, the DCC3 andthe DCC4) and sets three PDSCHs. The base station apparatus 100 alsouses the three PDSCHs, and transmits, to the mobile station apparatus200, the three downlink transport blocks using the three PDSCHs.Furthermore, the base station apparatus 100 associates the second PUCCHwith the PDCCH transmitted on the DCC3, and dynamically sets the secondPUCCH to the mobile station apparatus 200.

In the uplink subframe corresponding to the subframe #n+p, the mobilestation apparatus 200 transmits the control information of HARQ for (aplurality of) PDSCHs and/or (a plurality of) downlink transport blocksto the base station apparatus 100. In other words, the mobile stationapparatus 200 uses the two first PUCCHs selected (modified) according tothe DCC active set and/or the second PUCCH dynamically allocated, andthereby can transmit the control information of HARQ to the base stationapparatus 100. In this case, the mobile station apparatus 200 bundlesthe control information of HARQ, and can transmit it to the base stationapparatus 100. The mobile station apparatus 200 also multiplexes thecontrol information of HARQ, and can transmit it to the base stationapparatus 100.

Between the subframe #n+p and the subframe #n+q, the base stationapparatus 100 deactivates the five downlink carrier elements (the DCC1,the DCC2, the DCC3, the DCC4 and the DCC5). In this case, the four firstPUCCHs linked to the DCC1, the DCC2, the DCC4 and the DCC5 are set(allocated) to the mobile station apparatus 200.

As described above, in the second embodiment, the base station apparatus100 sets the DCC active set to the mobile station apparatus 200, and themobile station apparatus 200 activates (adds, maintains) and/orreleases, according to the DCC active set that is set by the basestation apparatus 100, the resources of the first PUCCHs, and uses thefirst PUCCHs and/or the second PUCCHs and thereby can transmit thecontrol information of HARQ to the base station apparatus 100. The basestation apparatus 100 sets the DCC active set to the mobile stationapparatus 200, and the mobile station apparatus 200 selects (modifies),according to the DCC active set that is set by the base stationapparatus 100, and uses the first PUCCHs and/or the second PUCCHs andthereby can transmit the control information of HARQ to the base stationapparatus 100. In this case, the mobile station apparatus 200 bundlesthe control information of HARQ, and can transmit it to the base stationapparatus 100. The mobile station apparatus 200 also multiplexes thecontrol information of HARQ, and can transmit it to the base stationapparatus 100.

As described above, the base station apparatus 100 and the mobilestation apparatus 200 transmit and receive the control information ofHARQ, and thus the base station apparatus 100 can set the first PUCCHsaccording to the DCC active set, with the result that it is possible toeffectively set the resources of the uplink. The base station apparatus100 also sets the first PUCCHs according to the DCC active set, and thusit is possible to effectively set the first PUCCHs for the mobilestation apparatus 200. Moreover, the mobile station apparatus 200bundles or multiplexes the control information of HARQ, and transmits itto the base station apparatus 100, and thus it is possible to reduce thetransmit power in the mobile station apparatus 200 and transmit thecontrol information of HARQ. The mobile station apparatus 200 uses anyone of (a small number of) (a plurality of) PUCCHs set by the basestation apparatus 100, and transmits the control information of HARQ,and thus it is possible to transmit the control information of HARQwhile reducing the transmit power in the mobile station apparatus 200.

In other words, when the base station apparatus 100 and the mobilestation apparatus 200 use a broadband frequency band composed of aplurality of carrier elements to perform communication, it is possibleto achieve the method of setting the resources by the base stationapparatus 100 and the effective transmission and reception of thecontrol information of HARQ with consideration given to the transmitpower in the mobile station apparatus 200. Although, here, in the secondembodiment, a description has been given of the example of the operationof the base station apparatus 100 and the mobile station apparatus 200in the mobile communication system that has been subjected to thesymmetric frequency band aggregation, the same method can be naturallyapplied to a mobile communication system that has been subjected toasymmetric frequency band aggregation.

A program that is operated in the mobile station apparatus 200 and thebase station apparatus 100 according to the present invention is aprogram (a program for making a computer function) for controlling a CPUand the like to achieve the functions of the present embodimentaccording to the present invention. Then, information handled by thesedevices is temporarily stored in a RAM after the processing, and then isstored in various ROMS and HDDs, is read by the CPU as necessary and issubjected to modification and writing. As a recording medium that storesthe program, any medium such as a semiconductor medium (for example, aROM or a nonvolatile memory card), an optical recording medium (forexample, a DVD, a MO, a MD, a CD or a BD) or a magnetic recording medium(for example, a magnetic tape or a flexible disc) may be used. Theprogram loaded is performed to achieve the functions of the presentembodiment described above, and, in addition, based on an instructionfrom the program, processing is performed either by an operating systemor together with another application program or the like, with theresult that the functions of the present invention may be achieved. Whenthe program is distributed in the market, the program can be stored in aportable recording medium and distributed or be transferred to a servercomputer connected through a network such as the Internet. In this case,a storage device of the server computer is also included in the presentinvention. Part or all of the mobile station apparatus 200 and the basestation apparatus 100 described above and according to the presentembodiment may be realized as an LSI that is a typical integratedcircuit. Each functional block of the mobile station apparatus 200 andthe base station apparatus 100 may be individually integrated into achip or part or all thereof may be integrated into a chip. The method ofachieving an integrated circuit is not limited to an LSI; it may beachieved by a dedicated circuit or a general-purpose processor. Whenadvances in the semiconductor technology produce a technology forachieving an integrated circuit instead of an LSI, it is also possibleto use the integrated circuit produced by such a technology. Althoughthe embodiment of the present invention has been described above indetail with reference to the drawings, the specific configuration is notlimited to this embodiment, and a design and the like without departingfrom the spirit of the present invention are also included in the scopeof claims. Although the embodiment of the present invention has beendescribed above in detail with reference to the drawings, the specificconfiguration is not limited to this embodiment, and a design and thelike without departing from the spirit of the present invention are alsoincluded in the scope of claims.

-   100 base station apparatus-   101 data control portion-   102 transmission data modulation portion-   103 radio portion-   104 scheduling portion-   105 channel estimation portion-   106 reception data demodulation portion-   107 data extraction portion-   108 higher layer-   109 antenna-   110 radio resource control portion-   200 (200-1, 200-2, 200-3) mobile station apparatus-   201 data control portion-   202 transmission data modulation portion-   203 radio portion-   204 scheduling portion-   205 channel estimation portion-   206 reception data demodulation portion-   207 data extraction portion-   208 higher layer-   209 antenna-   210 radio resource control portion

The invention claimed is:
 1. A base station apparatus which transmits,to a mobile station apparatus, a transport block using a physicaldownlink shared channel scheduled by using a physical downlink controlchannel, the base station apparatus comprising: a scheduling unitconfigured to configure a plurality of physical uplink control channelresources based on a parameter transmitted using a radio resourcecontrol signal, the plurality of physical uplink control channelresources being configured on an uplink component carrier on whichHybrid Automatic Repeat Request (HARQ) control information istransmitted using a physical uplink control channel; a determining unitconfigured to determine a physical uplink control channel resource onthe uplink component carrier for a physical downlink shared channeltransmission scheduled by using the physical downlink control channel ina subframe on a first downlink component carrier, the first downlinkcomponent carrier being activated and linked to the uplink componentcarrier, the physical uplink control channel resource being determinedbased on a control channel element of the physical downlink controlchannel, the determining unit configured to determine the physicaluplink control channel resource on the uplink component carrier for thephysical downlink shared channel transmission scheduled by using thephysical downlink control channel in the subframe on a second downlinkcomponent carrier, the second downlink component carrier being activatedand different from the first downlink component carrier, the physicaluplink control channel resource being determined from the plurality ofphysical uplink control channel resources which are configured; and areceiving unit configured to receive, from the mobile station apparatus,information bits using one of the determined physical uplink controlchannel resources, the information bits being used for indicating theHARQ control information for the transport block.
 2. The base stationapparatus according to claim 1, wherein the HARQ control information isinformation indicating ACK/NACK.
 3. The base station apparatus accordingto claim 2, wherein the HARQ control information is informationindicating DTX (discontinuous transmission).
 4. The base stationapparatus according to claim 1, wherein the HARQ control information isinformation indicating ACK/NACK.
 5. A mobile station apparatus whichreceives, from a base station apparatus, a transport block using aphysical downlink shared channel scheduled by using a physical downlinkcontrol channel, the mobile station apparatus comprising: a schedulingunit configured to configure a plurality of physical uplink controlchannel resources based on a parameter received using a radio resourcecontrol signal, the plurality of physical uplink control channelresources being configured on an uplink component carrier on whichHybrid Automatic Repeat Request (HARQ) control information istransmitted using a physical uplink control channel; a determining unitconfigured to determine a physical uplink control channel resource onthe uplink component carrier for a physical downlink shared channeltransmission indicated by a detection of the physical downlink controlchannel in a subframe on a first downlink component carrier, the firstdownlink component carrier being activated and linked to the uplinkcomponent carrier, the physical uplink control channel resource beingdetermined based on a control channel element of the physical downlinkcontrol channel, the determining unit configured to determine thephysical uplink control channel resource on the uplink component carrierfor the physical downlink shared channel transmission indicated by thedetection of the physical downlink control channel in the subframe on asecond downlink component carrier, the second downlink component carrierbeing activated and different from the first downlink component carrier,the physical uplink control channel resource being determined from theplurality of physical uplink control channel resources which areconfigured; and a transmitting unit configured to transmit, to the basestation apparatus, information bits using one of the determined physicaluplink control channel resources, the information bits being used forindicating the HARQ control information for the transport block.
 6. Themobile station apparatus according to claim 5, wherein the HARQ controlinformation is information indicating ACK/NACK.
 7. The mobile stationapparatus according to claim 6, wherein the HARQ control information isinformation indicating DTX (discontinuous transmission).
 8. The mobilestation apparatus according to claim 5, wherein the HARQ controlinformation is information indicating DTX (discontinuous transmission).